Means for extinguishing arcs.



No. 766,187. I PATENTED AUG. 2, 1904.

R. r. HELLMUNDI MEANS FOR EXTINGUISHING ARCS.

APPLICATION FILED NOV. 28, 1903.

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WITNESSES;

2;, 0 7 Q @JF INVENTOR A TTOHNE Y PATENTED AUG. 2, 1904.

R. E. HELLMUND. MEANS FOR EXTINGUISHING ARCS.

APPLIOATION FILED NOV. 28, 1903.

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UNITED STATES Patented August 2, 1904:.

RUDOLF E. HELLMUND, OF NEW YORK, N. Y.

MEANS FOR EXTINGUISHING ARCS- SPECIFIGATION forming part of Letters Patent No. 766,187, dated August 2, 1904.

Application filed November 28, 1903. Serial No. 182,998. (No model.) 7

' To all whom it may concern:

Be it known that I, RUDoLr E. HELLMUN-D, of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Means for Extinguishing Arcs; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

On interrupting electric circuits by means of switches, circuit-breakers, cut-outs, and similar appliances there is produced between the separated parts sparking or arcing, which results in destructive burning of the contacts and, moreover, prevents a quick or instantaneous interruption of the circuit. To overcome this destructive sparking, various means have heretofore been employed for disrupting and extinguishing the are, such means comprising blasts of air or other gas or certain quantities of liquid directed against the are or the place where the arc would form such, for instance, as a weakened point in a fuse or at a point Where a switch-blade withdraws from its contact or terminal; but all these means just cited render necessary the employment of air and water tight appliances. Furthermore, when air or other gas is used it becomes necessary to compress the air and to compress the gas or to evolve it by heat or the explosion of a gas-producing mixture, all of which involves considerable complications and expensive constructions and in some instances the repeated renewals of the gas producing charge, and when liquid is used the same will evaporate or otherwise deteriorate with age, also involving considerable attention and renewal.

In contradistinction to the above-named means for extinguishing arcs the object of my invention is to provide means for positively projecting a quantity of pulverulent substance, such as sand, between the separated parts of the switch or fuse when and at the very instant such parts are separated, this means manifestly requiring no air or water tight receptacle and possessing the further advantage that it can be used for an indefinite time without renewing the sand.

In the accompanying drawings, which illustrate the invention as applied to a fuse and to a switch, Figure 1 is a side elevation of a fuse-box embodying the invention. Fig. 2 is a similar view with the cover-plate removed. Fig. 3 is a vertical transverse section of the fuse-box. Fig. 4. is a side elevation of a switch embodying the invention. Fig. 5 is a longitudinal vertical section of the switch with the interior parts in side elevation. Fig. 6 is a vertical transverse section.

Referring now particularly to Figs. 1, 2, and 3, 1 designates a fuse box or casing provided with an extension 2, from which projects a ledge 3, supporting a binding-post 4, from which depends a socket 5, designed to receive one end of a fuse-link 6. The casing is formed with an opening 7 through which the fuse passes, and the other end of the latter is held in a socket 8, secured on the periphery of a wheel 9, mounted to turn around an axis 10 and provided with a plurality of blades 11. On the axis 10 is a finger 12, to which is secured one end of a helical spring 13, and the other end of said spring is secured to a studl4 contiguous to the socket 8. The said spring 13, while primarily designed to turn the wheel 9 in one direction, also serves as an electrical conductor between the fuse and the axis 10, which latter is preferably secured rigid with the cover-plate 15 of the casing and in contact with the binding-post 16, mounted thereon. By this arrangement the spring 13 may be wound tense in the operation of screwing the cover-plate 15 in place on the casing.

The casing 1 is designed to contain sand or similar pulverulent substances 16, as illus trated in Fig. 2. Hence in practical operation when the fuse 6 melts and parts the wheel, being then free to turn under the influence of its spring, will rotate, and its blades will project a quantity of sand across the are caused by the separation of the parts of the fuse, and will thus instantly extinguish the arc, while at the same time quickly carrying one part of the fuse away from the other, which assists in disrupting the are. It is of course understood that under normal conditions so long as the fuse remains integral and not melted its tensile strength is sufficient to withstand the tension of the spring 13.

Referring now to Figs. 4:, 5, and 6, which illustrate the invention embodied in a switch, 17 designates a receptacle intended to contain sand 18 to the level, preferably as indicated in the drawings, and 19 designates a coverplate to which is secured two binding-posts 20 21, one of which carries a contact or terminal 22 inside the receptacle and the other of which carries an ear 23, to which is pivoted a switch-blade 2a. The blade 24 is adapted to swing into and out of contact with the terminal 22 and is provided with a handle portion 25, projecting outside of the receptacle 17, and it is also formed with a slot 26, in which is received a crank 27, extending from a revoluble shaft 28, provided with a plurality of blades 29. From the above description it will be seen that when the blade 24 is moved out of contact with the terminal 22 to open the circuit its movement, transmitted through the crank 27, will cause the blades 29 to sweep through the sand and project a quantity of it across the are, instantly extinguishing the same.

It is to be noted that the level of the sand in the receptacle 17 is below the lower end of the terminal 22, leaving an air-space between the latter and the sand. Hence, as is manifest, it is not necessary that the sand be kept perfectly dry or that it be absolutely insulating in character.

In some instances where the invention is embodied in a switch or other apparatus the axis and blades may be dispensed with, and the switch-blade or other parts opening the circuit may be depended upon to splash the sand when it strikes the same across the arc.

I claim as my invention 1. In an electric circuit, the combination of a receptacle designed to contain sand, means for maintaining an electric circuit, and means for projecting a quantity of sand to extinguish the are when such circuit is opened.

2. In an electric circuit, the combination of means for opening or breaking the circuit, and means for automatically projecting a quantity of sand across the arc atthe instant the circuit is opened.

3. In a device of the character described, a receptacle containing sand, means for maintaining an electric circuit through the receptacle, and an automatic revoluble device arranged to project a quantity of the sand across the are when the circuit is opened.

4:. A device of the character described, comprising a receptacle containing a pulverulent substance such as sand, means in said receptacle for maintaining an electric circuit and for opening such circuit, and revoluble blades adapted to project a quantity of the sand across the are when the circuit is opened.

5. In an electric circuit, the combination of means for opening or breaking the circuit, said means being arranged to move a body or quantity of pulverulent substance in proximity to the are at the instant the circuit is opened.

6. In an electric circuit, the combination of means for opening or breaking the circuit, and

mechanical means for moving a quantity of pulverulent substance near the are, there being a connection between the circuit opening means and said other means whereby they will act simultaneously.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses,

RUDOLF E. HELLMUND. Witnesses:

FREDERICK S. STITT, GRAFTON L. MCGILL. 

